Kievan Rus'
Many Kievan Rus' epic poems, called Bylinas, prominently featured stories about these heroes, as did several chronicles, including the 13 century Galician–Volhynian Chronicle. Some of bogatyrs are presumed to be historical figures, while others, like the giant Sviatogor, are purely fictional and possibly descend from Slavic pagan mythology.
Most of stories about bogatyrs revolve around the court of Vladimir I of Kiev (958–1015). There served the most notable bogatyrs or vityazs: the trio of Alyosha Popovich, Dobrynya Nikitich and Ilya Muromets. Each of them tend to be known for a certain character trait: Alyosha Popovich for his wits, Dobrynya Nikitich for his courage, and Ilya Muromets for his physical and spiritual power and integrity, and for his dedication to the protection of his homeland and people.
An early usage of the word bogatyr was recorded in Sernitskiy's book "Descriptio veteris et novae Poloniae cum divisione ejusdem veteri et nova," ("A description of the Old and the New Poland with the old, and a new division of the same,") printed in 1585 in an unknown location, in which he says, "Rossi… de heroibus suis, quos Bohatiros id est semideos vocant, aliis persuadere conantur." ("Russians... to the heroes of them, whom that Bohatirs called to their demigods, they try to persuade others.")
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